{
  "id": "1705.09266",
  "version": "v1",
  "published": "2017-05-25T17:15:44.000Z",
  "updated": "2017-05-25T17:15:44.000Z",
  "title": "Analysis of single and composite structural defects in pure amorphous silicon: a first-principles study",
  "authors": [
    "Yoritaka Furukawa",
    "Yu-ichiro Matsushita"
  ],
  "categories": [
    "cond-mat.mtrl-sci"
  ],
  "abstract": "The structural and electronic properties of amorphous silicon ($a$-Si) are investigated by first-principles calculations based on the density-functional theory (DFT), focusing on the intrinsic structural defects. By simulated melting and quenching of a crystalline silicon model through the Car-Parrinello molecular dynamics (CPMD), we generate several different $a$-Si samples, in which three-fold ($T_3$), five-fold ($T_5$), and anomalous four-fold ($T_{4a}$) defects are contained. Using the samples, we clarify how the disordered structure of $a$-Si affects the characters of its density of states (DOS). We subsequently study the properties of defect complexes found in the obtained samples, including one that comprises three $T_5$ defects, and we show the conditions for the defect complexes to be energetically stable. Finally, we investigate the hydrogen passivation process of the $T_5$ defects in $a$-Si and show that the hydrogenation of $T_5$ is an exothermic reaction and that the activation energy for a H$_2$ molecule to passivate two $T_5$ sites is calculated to be 1.05 eV.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2017-05-25T17:15:44.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "composite structural defects",
      "pure amorphous silicon",
      "first-principles study",
      "defect complexes",
      "car-parrinello molecular dynamics"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}